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Murakami Y, Fahmy S, Goldblum RM, Watson CS, Midoro-Horiuti T. Environmental estrogen exposures alter molecular signaling in immune cells that promote the development of childhood asthma. Mol Immunol 2023; 157:142-145. [PMID: 37023493 PMCID: PMC10149617 DOI: 10.1016/j.molimm.2023.03.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 02/01/2023] [Accepted: 03/26/2023] [Indexed: 04/08/2023]
Abstract
Environmental estrogens (EEs) are associated with an increased prevalence of asthma. These epigenetic alterations of the immune cells may explain the multigenerational effects on asthma development. We hypothesized that exposure to immune cells enhances allergic sensitization by initiating signaling in these cells. Human T cell lines (TIB-152, CCL-119) were exposed to varying concentrations of estradiol, bisphenol A, bisphenol S, or bisphenol A + estradiol. H3K27me3, phosphorylations of EZH2 (pEZH2), AKT (pAKT), and phosphatidylinositide 3-kinase (pPI3K) were assessed. pAKT and pPI3K were decreased in response to some of the concentrations of these exposures in both cell lines. It is likely that EEs exposure to immune cells is one of the factors in the increase in the prevalence of asthma.
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Affiliation(s)
- Yoko Murakami
- Department of Pediatrics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA
| | - Sahar Fahmy
- Department of Pediatrics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA
| | - Randall M Goldblum
- Department of Pediatrics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA; Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645, USA
| | - Cheryl S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645, USA
| | - Terumi Midoro-Horiuti
- Department of Pediatrics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA.
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2
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Shugar DH, Jacquemart M, Shean D, Bhushan S, Upadhyay K, Sattar A, Schwanghart W, McBride S, de Vries MVW, Mergili M, Emmer A, Deschamps-Berger C, McDonnell M, Bhambri R, Allen S, Berthier E, Carrivick JL, Clague JJ, Dokukin M, Dunning SA, Frey H, Gascoin S, Haritashya UK, Huggel C, Kääb A, Kargel JS, Kavanaugh JL, Lacroix P, Petley D, Rupper S, Azam MF, Cook SJ, Dimri AP, Eriksson M, Farinotti D, Fiddes J, Gnyawali KR, Harrison S, Jha M, Koppes M, Kumar A, Leinss S, Majeed U, Mal S, Muhuri A, Noetzli J, Paul F, Rashid I, Sain K, Steiner J, Ugalde F, Watson CS, Westoby MJ. A massive rock and ice avalanche caused the 2021 disaster at Chamoli, Indian Himalaya. Science 2021; 373:300-306. [PMID: 34112725 DOI: 10.1126/science.abh4455] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/27/2021] [Indexed: 11/02/2022]
Abstract
On 7 February 2021, a catastrophic mass flow descended the Ronti Gad, Rishiganga, and Dhauliganga valleys in Chamoli, Uttarakhand, India, causing widespread devastation and severely damaging two hydropower projects. More than 200 people were killed or are missing. Our analysis of satellite imagery, seismic records, numerical model results, and eyewitness videos reveals that ~27 × 106 cubic meters of rock and glacier ice collapsed from the steep north face of Ronti Peak. The rock and ice avalanche rapidly transformed into an extraordinarily large and mobile debris flow that transported boulders greater than 20 meters in diameter and scoured the valley walls up to 220 meters above the valley floor. The intersection of the hazard cascade with downvalley infrastructure resulted in a disaster, which highlights key questions about adequate monitoring and sustainable development in the Himalaya as well as other remote, high-mountain environments.
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Affiliation(s)
- D H Shugar
- Water, Sediment, Hazards, and Earth-surface Dynamics (waterSHED) Lab, Department of Geoscience, University of Calgary, AB, Canada.
| | - M Jacquemart
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Laboratory of Hydraulics, Hydrology, and Glaciology (VAW), ETH Zurich, Zurich, Switzerland.,Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - D Shean
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - S Bhushan
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - K Upadhyay
- Independent journalist/water policy researcher, Nainital, Uttarakhand, India
| | - A Sattar
- Department of Geography, University of Zurich, Zurich, Switzerland
| | - W Schwanghart
- Institute of Environmental Science and Geography, University of Potsdam, Potsdam, Germany
| | - S McBride
- U.S. Geological Survey, Earthquake Science Center, Moffett Field, CA, USA
| | - M Van Wyk de Vries
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, MN, USA.,St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA
| | - M Mergili
- Institute of Geography and Regional Science, University of Graz, Graz, Austria.,Institute of Applied Geology, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - A Emmer
- Institute of Geography and Regional Science, University of Graz, Graz, Austria
| | - C Deschamps-Berger
- Centre d'Etudes Spatiales de la Biosphère (CESBIO), Université de Toulouse, CNES/CNRS/INRAE/IRD/UP, Toulouse, France
| | - M McDonnell
- Department of Geography, University of Utah, Salt Lake City, Utah, USA
| | - R Bhambri
- Department of Geography, South Asia Institute, Heidelberg University, Heidelberg, Germany
| | - S Allen
- Department of Geography, University of Zurich, Zurich, Switzerland.,Institute for Environmental Sciences, University of Geneva, Switzerland
| | - E Berthier
- Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), Université de Toulouse, CNES/CNRS/IRD/UPS, Toulouse, France
| | - J L Carrivick
- School of Geography, University of Leeds, Leeds, West Yorkshire, UK.,water@leeds, University of Leeds, Leeds, West Yorkshire, UK
| | - J J Clague
- Department of Earth Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - M Dokukin
- Department of Natural Disasters, High-Mountain Geophysical Institute, Nalchik, Russia
| | - S A Dunning
- School of Geography, Politics, and Sociology, Newcastle University, Newcastle, UK
| | - H Frey
- Department of Geography, University of Zurich, Zurich, Switzerland
| | - S Gascoin
- Centre d'Etudes Spatiales de la Biosphère (CESBIO), Université de Toulouse, CNES/CNRS/INRAE/IRD/UP, Toulouse, France
| | - U K Haritashya
- Department of Geology and Environmental Geosciences, University of Dayton, Dayton, OH, USA
| | - C Huggel
- Department of Geography, University of Zurich, Zurich, Switzerland
| | - A Kääb
- Department of Geosciences, University of Oslo, Oslo, Norway
| | - J S Kargel
- Planetary Science Institute, Tucson, AZ, USA
| | - J L Kavanaugh
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB, Canada
| | - P Lacroix
- ISTerre, Université Grenoble Alpes, IRD, CNRS, Grenoble, France
| | - D Petley
- Department of Geography, The University of Sheffield, Sheffield, UK
| | - S Rupper
- Department of Geography, University of Utah, Salt Lake City, Utah, USA
| | - M F Azam
- Indian Institute of Technology Indore, Madhya Pradesh, Indore, India
| | - S J Cook
- Department of Geography and Environmental Science, University of Dundee, Dundee, UK.,United Nations Educational, Scientific and Cultural Organization (UNESCO) Centre for Water Law, Policy, and Science, University of Dundee, Dundee, UK
| | - A P Dimri
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - M Eriksson
- Stockholm International Water Institute, Stockholm, Sweden
| | - D Farinotti
- Laboratory of Hydraulics, Hydrology, and Glaciology (VAW), ETH Zurich, Zurich, Switzerland.,Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
| | - J Fiddes
- WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
| | - K R Gnyawali
- School of Engineering, University of British Columbia, Kelowna, BC, Canada
| | - S Harrison
- College of Life and Environmental Sciences, University of Exeter, Penryn, UK
| | - M Jha
- Department of Mines and Geology, National Earthquake Monitoring and Research Center, Kathmandu, Nepal
| | - M Koppes
- Department of Geography, University of British Columbia, Vancouver, BC, Canada
| | - A Kumar
- Wadia Institute of Himalayan Geology, Dehradun, Uttarakhand, India
| | - S Leinss
- Institute of Environmental Engineering (IfU), ETH Zurich, 8093 Zürich, Switzerland
| | - U Majeed
- Department of Geoinformatics, University of Kashmir, Hazratbal Srinagar, Jammu and Kashmir, India
| | - S Mal
- Department of Geography, Shaheed Bhagat Singh College, University of Delhi, Delhi, India
| | - A Muhuri
- Centre d'Etudes Spatiales de la Biosphère (CESBIO), Université de Toulouse, CNES/CNRS/INRAE/IRD/UP, Toulouse, France.,Institute of Geography, Heidelberg University, Germany
| | - J Noetzli
- WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland
| | - F Paul
- Department of Geography, University of Zurich, Zurich, Switzerland
| | - I Rashid
- Department of Geoinformatics, University of Kashmir, Hazratbal Srinagar, Jammu and Kashmir, India
| | - K Sain
- Wadia Institute of Himalayan Geology, Dehradun, Uttarakhand, India
| | - J Steiner
- International Centre for Integrated Mountain Development, Kathmandu, Nepal.,Department of Physical Geography, Utrecht University, Netherlands
| | - F Ugalde
- Geoestudios, San José de Maipo, Chile.,Department of Geology, University of Chile, Santiago, Chile
| | - C S Watson
- Centre for Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET), School of Earth and Environment, University of Leeds, Leeds, UK
| | - M J Westoby
- Department of Geography and Environmental Sciences, Northumbria University, Newcastle upon Tyne, UK
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Saraf MK, Jeng YJ, Watson CS. Nongenomic effects of estradiol vs. the birth control estrogen ethinyl estradiol on signaling and cell proliferation in pituitary tumor cells, and differences in the ability of R-equol to neutralize or enhance these effects. Steroids 2021; 168:108411. [PMID: 31132367 DOI: 10.1016/j.steroids.2019.01.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 01/24/2019] [Indexed: 12/19/2022]
Abstract
Ethinyl estradiol (EE2, the active component of many birth control formulations) persists in treated waste waters and it has become a concerning endocrine-disrupting contaminant throughout the world. Previous studies have not examined the behavior of EE2 in nongenomic signaling pathways and the subsequent functional responses (either alone or in mixtures) or conducted comparisons with the physiological estrogen estradiol (E2). In this study, mitogen-activated protein kinases (MAPKs), ERK, and JNK were activated in pituitary tumor cells by fM EE2, but p38 activation was insensitive to <nM doses. Both E2 and EE2 (10 fM to 10 nM) caused cell proliferation as well as triggering intracellular calcium increases and GTP charging of Gαi. E2 was more effective at causing prolactin release. Previously, we reported that the soy-based diadzein synthetic metabolite R-equol (R-eq) activated nongenomic responses in pituitary cells and impaired the actions of E2, thereby affecting both prolactin release and cell proliferation. In the present study, as expected, R-eq activated all MAPKs in a dose-dependent manner at concentrations ranging from fM to 100 nm, and it also modified the effects of environmentally and therapeutically relevant levels of EE2. The physiological/therapeutic doses of E2/EE2 that activated p38 were most effectively challenged by R-eq at ≥fM concentrations. R-eq did not alter the proliferative response to E2 but it elevated the cell numbers induced by EE2 at all concentrations of added R-eq. The more pronounced ability of R-eq to inhibit the cell-killing mechanisms associated with p38-induced inflammatory responses may explain its capacity to increase the numbers of EE2-stimulated pituitary tumor cells. Thus, widespread exposure to persistent pharmaceutical estrogens that imperfectly mimic endogenous estrogens may exacerbate cell proliferation in these responsive cells.
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Affiliation(s)
- Manish Kumar Saraf
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch Galveston, TX 77555-0645, United States
| | - Yow-Jiun Jeng
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch Galveston, TX 77555-0645, United States
| | - Cheryl S Watson
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch Galveston, TX 77555-0645, United States.
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Watson CS, Koong L, Jeng YJ, Vinas R. Xenoestrogen interference with nongenomic signaling actions of physiological estrogens in endocrine cancer cells. Steroids 2019; 142:84-93. [PMID: 30012504 PMCID: PMC6339598 DOI: 10.1016/j.steroids.2018.06.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/15/2018] [Accepted: 06/27/2018] [Indexed: 11/20/2022]
Abstract
Rapid nongenomic signaling by estrogens (Es), initiated near the cell membrane, provides new explanations for the potent actions of environmental chemicals that imperfectly mimic physiological Es. These pathways can affect tumor growth, stabilization, or shrinkage via a number of signaling streams such as activation/inactivation of mitogen-activated protein kinases and caspases, generation of second messengers, and phospho-triggering of cyclin instability. Though prostate cancers are better known for their responsiveness to androgen deprivation, ∼17% of late stage tumors regress in response to high dose natural or pharmaceutical Es; however, the mechanisms at the cellular level are not understood. More accurate recent measurements show that estradiol (E2) levels decline in aging men, leading to the hypothesis that maintaining young male levels of E2 may prevent the growth of prostate cancers. Major contributions to reducing prostate cancer cell numbers included low E2 concentrations producing sustained ERK phospho-activation correlated with generation of reactive oxygen species causing cancer cell death, and phospho-activation of cyclin D1 triggering its rapid degradation by interrupting cell cycle progression. These therapeutic actions were stronger in early stage tumor cells (with higher membrane estrogen receptor levels), and E2 was far more effective compared to diethylstilbestrol (the most frequently prescribed E treatment). Xenoestrogens (XEs) exacerbated the growth of prostate cancer cells, and as we know from previous studies in pituitary cancer cells, can interfere with the nongenomic signaling actions of endogenous Es. Therefore, nongenomic actions of physiological levels of E2 may be important deterrents to the growth of prostate cancers, which could be undermined by the actions of XEs.
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Affiliation(s)
- Cheryl S Watson
- Biochemistry & Molecular Biology Dept., University of Texas Medical Branch, Galveston, TX 77555, United States.
| | - Luke Koong
- Biochemistry & Molecular Biology Dept., University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Yow-Jiun Jeng
- Biochemistry & Molecular Biology Dept., University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Rene Vinas
- Biochemistry & Molecular Biology Dept., University of Texas Medical Branch, Galveston, TX 77555, United States
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Soto CA, Shashack MJ, Fox RG, Bubar MJ, Rice KC, Watson CS, Cunningham KA, Gilbertson SR, Anastasio NC. Novel Bivalent 5-HT 2A Receptor Antagonists Exhibit High Affinity and Potency in Vitro and Efficacy in Vivo. ACS Chem Neurosci 2018; 9:514-521. [PMID: 29111677 DOI: 10.1021/acschemneuro.7b00309] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The 5-HT2A receptor (5-HT2AR) plays an important role in various neuropsychiatric disorders, including substance use disorder and schizophrenia. Homodimerization of this receptor has been suggested, but tools that allow direct assessment of the relevance of the 5-HT2AR:5-HT2AR homodimer in these disorders are necessary. We chemically modified the selective 5-HT2AR antagonist M100907 to synthesize a series of homobivalent ligands connected by ethylene glycol linkers of varying lengths that may be useful tools for probing 5-HT2AR:5-HT2AR homodimer function. We tested these molecules for 5-HT2AR antagonist activity in a cell line stably expressing the functional 5-HT2AR and quantified a downstream signaling target, activation (phosphorylation) of extracellular regulated kinases 1/2 (ERK1/2), in comparison to in vivo efficacy of altering spontaneous or cocaine-evoked locomotor activity in rats. All of the synthetic compounds inhibited 5-HT-mediated phosphorylation of ERK1/2 in the cellular signaling assay; the potency of the bivalent ligands varied as a function of linker length, with the intermediate linker lengths being the most potent. The Ki values for the binding of bivalent ligands to 5-HT2AR were only slightly lower than the values for the parent (+)-M100907 compound, but significant selectivity for 5-HT2AR over 5-HT2BR or 5-HT2CR binding was retained. In addition, the 11-atom-linked bivalent 5-HT2AR antagonist (2 mg/kg, intraperitoneally) demonstrated efficacy on par with that of (+)-M100907 in inhibiting cocaine-evoked hyperactivity. As we develop further strategies for ligand-evoked receptor assembly and analyses of diverse signaling and functional roles, these novel homobivalent 5-HT2AR antagonist ligands will serve as useful in vitro and in vivo probes of 5-HT2AR structure and function.
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Affiliation(s)
| | | | | | | | - Kenner C. Rice
- Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland 20892, United States
| | | | | | - Scott R. Gilbertson
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
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Saraf MK, Jeng YJ, Watson CS. R-equol, a synthetic metabolite of the dietary estrogen daidzein, modulates the nongenomic estrogenic effects of 17β-estradiol in pituitary tumor cells. ACTA ACUST UNITED AC 2016. [DOI: 10.1080/23273747.2016.1226697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Koong LY, Watson CS. Rapid, nongenomic signaling effects of several xenoestrogens involved in early- vs. late-stage prostate cancer cell proliferation. ACTA ACUST UNITED AC 2015. [DOI: 10.4161/23273747.2014.995003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Luke Y Koong
- Biochemistry & Molecular Biology Department; University of Texas Medical Branch; Galveston, TX USA
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Midoro-Horiuti T, Choudhury BK, Vinas R, Watson CS, Goldblum RM. Environmental Estrogens Alter Signaling in Immune Cells That Promotes the Development of Childhood Asthma. J Allergy Clin Immunol 2015. [DOI: 10.1016/j.jaci.2014.12.1445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
BACKGROUND Diethylstilbestrol (DES) and other pharmaceutical estrogens have been used at ≥ µM concentrations to treat advanced prostate tumors, with successes primarily attributed to indirect hypothalamic-pituitary-testicular axis control mechanisms. However, estrogens also directly affect tumor cells, though the mechanisms involved are not well understood. METHODS LAPC-4 (androgen-dependent) and PC-3 (androgen-independent) cell viability was measured after estradiol (E2) or DES treatment across wide concentration ranges. We then examined multiple rapid signaling mechanisms at 0.1 nM E2 and 1 µM DES optima including levels of: activation (phosphorylation) for mitogen-activated protein kinases, cell-cycle proteins, and caspase 3, necroptosis, and reactive oxygen species (ROS). RESULTS LAPC-4 cells were more responsive than PC-3 cells. Robust and sustained extracellular-regulated kinase activation with E2 , but not DES, correlated with ROS generation and cell death. c-Jun N-terminal kinase was only activated in E2-treated PC-3 cells and was not correlated with caspase 3-mediated apoptosis; necroptosis was not involved. The cell-cycle inhibitor protein p16(INK4A) was phosphorylated in both cell lines by both E2 and DES, but to differing extents. In both cell types, both estrogens activated p38 kinase, which subsequently phosphorylated cyclin D1, tagging it for degradation, except in DES-treated PC-3 cells. CONCLUSIONS Cyclin D1 status correlated most closely with disrupted cell cycling as a cause of reduced cell numbers, though other mechanisms also contributed. As low as 0.1 nM E2 effectively elicited these mechanisms, and its use could dramatically improve outcomes for both early- and late-stage prostate cancer patients, while avoiding the side effects of high-dose DES treatment.
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Affiliation(s)
- Luke Y Koong
- Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, Texas
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Viñas R, Goldblum RM, Watson CS. Rapid estrogenic signaling activities of the modified (chlorinated, sulfonated, and glucuronidated) endocrine disruptor bisphenol A. ACTA ACUST UNITED AC 2014. [DOI: 10.4161/endo.25411] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Gore AC, Balthazart J, Bikle D, Carpenter DO, Crews D, Czernichow P, Diamanti-Kandarakis E, Dores RM, Grattan D, Hof PR, Hollenberg AN, Lange C, Lee AV, Levine JE, Millar RP, Nelson RJ, Porta M, Poth M, Power DM, Prins GS, Ridgway EC, Rissman EF, Romijn JA, Sawchenko PE, Sly PD, Söder O, Taylor HS, Tena-Sempere M, Vaudry H, Wallen K, Wang Z, Wartofsky L, Watson CS. Policy decisions on endocrine disruptors should be based on science across disciplines: a response to Dietrich et al. Horm Res Paediatr 2014; 80:305-8. [PMID: 24107550 DOI: 10.1159/000355668] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- A C Gore
- Division of Pharmacology and Toxicology, The University of Texas, Austin, Tex., USA
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Abstract
Some chemicals used in consumer products or manufacturing (e.g. plastics, surfactants, pesticides, resins) have estrogenic activities; these xenoestrogens (XEs) chemically resemble physiological estrogens and are one of the major categories of synthesized compounds that disrupt endocrine actions. Potent rapid actions of XEs via nongenomic mechanisms contribute significantly to their disruptive effects on functional endpoints (e.g. cell proliferation/death, transport, peptide release). Membrane-initiated hormonal signaling in our pituitary cell model is predominantly driven by mERα with mERβ and GPR30 participation. We visualized ERα on plasma membranes using many techniques in the past (impeded ligands, antibodies to ERα) and now add observations of epitope proximity with other membrane signaling proteins. We have demonstrated a range of rapid signals/protein activations by XEs including: calcium channels, cAMP/PKA, MAPKs, G proteins, caspases, and transcription factors. XEs can cause disruptions of the oscillating temporal patterns of nongenomic signaling elicited by endogenous estrogens. Concentration effects of XEs are nonmonotonic (a trait shared with natural hormones), making it difficult to design efficient (single concentration) toxicology tests to monitor their harmful effects. A plastics monomer, bisphenol A, modified by waste treatment (chlorination) and other processes causes dephosphorylation of extracellular-regulated kinases, in contrast to having no effects as it does in genomic signaling. Mixtures of XEs, commonly found in contaminated environments, disrupt the signaling actions of physiological estrogens even more severely than do single XEs. Understanding the features of XEs that drive these disruptive mechanisms will allow us to redesign useful chemicals that exclude estrogenic or anti-estrogenic activities.
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Affiliation(s)
- Cheryl S Watson
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Guangzhen Hu
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
| | - Adriana A Paulucci-Holthauzen
- Center for Biomedical Engineering, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, USA.
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Gore AC, Balthazart J, Bikle D, Carpenter DO, Crews D, Czernichow P, Diamanti-Kandarakis E, Dores RM, Grattan D, Hof PR, Hollenberg AN, Lange C, Lee AV, Levine JE, Millar RP, Nelson RJ, Porta M, Poth M, Power DM, Prins GS, Ridgway EC, Rissman EF, Romijn JA, Sawchenko PE, Sly PD, Söder O, Taylor HS, Tena-Sempere M, Vaudry H, Wallen K, Wang Z, Wartofsky L, Watson CS. Reprint of: policy decisions on endocrine disruptors should be based on science across disciplines: a response to Dietrich et al. Horm Behav 2014; 65:190-3. [PMID: 24289987 DOI: 10.1016/j.yhbeh.2013.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- A C Gore
- Division of Pharmacology and Toxicology, The University of Texas, Austin, TX 78712, USA.
| | - J Balthazart
- University of Liège, GIGA Neurosciences, B-4000 Liège, Belgium
| | - D Bikle
- VA Medical Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - D O Carpenter
- Institute for Health and the Environment, University at Albany, State University of New York, Albany, NY 12222, USA
| | - D Crews
- Section of Integrative Biology, The University of Texas, Austin, TX 78712, USA
| | | | | | - R M Dores
- Department of Biological Sciences, University of Denver, Denver, CO 80208, USA
| | - D Grattan
- Department of Anatomy, University of Otago, North Dunedin 9016, New Zealand
| | - P R Hof
- Icahn School of Medicine at Mt Sinai, New York, NY 10029, USA
| | - A N Hollenberg
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - C Lange
- University of Minnesota Masonic Cancer Center, Minneapolis, MN 55455, USA
| | - A V Lee
- University of Pittsburgh Cancer Institute, Magee Women's Research Institute, Pittsburgh, PA 15213, USA
| | - J E Levine
- Wisconsin National Primate Research Center, Madison, WI 53715, USA
| | - R P Millar
- UCT/MRC Receptor Biology Unit, University of Cape Town, Cape Town, South Africa
| | - R J Nelson
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - M Porta
- Hospital del Mar Institute of Medical Research, School of Medicine, Universitat Autònoma de Barcelona, 080041 Barcelona, Spain
| | - M Poth
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - D M Power
- Department of Biosciences, Universidade do Algarve, 8005-139 Faro, Portugal
| | - G S Prins
- Department of Physiology and Biophysics, University of Illinois, Chicago, IL 60612, USA
| | - E C Ridgway
- Department of Medicine, University of Colorado School of Medicine, Denver, CO 80208, USA
| | - E F Rissman
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, VA 22908, USA
| | - J A Romijn
- Division of Medicine, Academic Medical Center, University of Amsterdam, 1012 WX Amsterdam, The Netherlands
| | - P E Sawchenko
- Laboratory of Neuronal Structure and Function, The Salk Institute, La Jolla, CA 92037, USA
| | - P D Sly
- Queensland Children's Medical Institute, University of Queensland, Royal Children's Hospital, Brisbane, Queensland 4000, Australia
| | - O Söder
- Karolinska Institutet at Karolinska University Hospital Solna, 171 76 Stockholm, Sweden
| | - H S Taylor
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT 06510, USA
| | - M Tena-Sempere
- Department of Cell Biology and Physiology, University of Córdoba, 14071 Córdoba, Spain
| | - H Vaudry
- Institut National de la Santé et de la Recherche Médicale U982, University of Rouen, 76821 Rouen, France
| | - K Wallen
- Department of Psychology, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - Z Wang
- Department of Psychology and Neuroscience, Florida State University, Tallahassee, FL 32306, USA
| | - L Wartofsky
- Department of Medicine, Washington Hospital Center, Washington, DC 20010, USA
| | - C S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
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14
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Gore AC, Balthazart J, Bikle D, Carpenter DO, Crews D, Czernichow P, Diamanti-Kandarakis E, Dores RM, Grattan D, Hof PR, Hollenberg AN, Lange C, Lee AV, Levine JE, Millar RP, Nelson RJ, Porta M, Poth M, Power DM, Prins GS, Ridgway EC, Rissman EF, Romijn JA, Sawchenko PE, Sly PD, Söder O, Taylor HS, Tena-Sempere M, Vaudry H, Wallen K, Wang Z, Wartofsky L, Watson CS. Reprint of: policy decisions on endocrine disruptors should be based on science across disciplines: a response to Dietrich, et al. Front Neuroendocrinol 2014; 35:2-5. [PMID: 24268499 DOI: 10.1016/j.yfrne.2013.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 09/17/2013] [Indexed: 11/24/2022]
Affiliation(s)
- A C Gore
- Pharmacology and Toxicology, The University of Texas at Austin, Austin, TX 78712, United States.
| | - J Balthazart
- University of Liège, GIGA Neurosciences, B-4000 Liège, Belgium
| | - D Bikle
- VA Medical Center and University of California, San Francisco, San Francisco, CA 94143, United States
| | - D O Carpenter
- Institute for Health and the Environment, University at Albany, State University of New York, Albany, NY 12222, United States
| | - D Crews
- Section of Integrative Biology, The University of Texas, Austin, TX 78712, United States
| | - P Czernichow
- Professor Emeritus of Pediatrics, University of Paris, 75006 Paris, France
| | | | - R M Dores
- Department of Biological Sciences, University of Denver, Denver, CO 80208, United States
| | - D Grattan
- Department of Anatomy, University of Otago, North Dunedin 9016, New Zealand
| | - P R Hof
- Icahn School of Medicine at Mt Sinai, New York, NY 10029, United States
| | | | - C Lange
- University of Minnesota Masonic Cancer Center, Minneapolis, MN 55455, United States
| | - A V Lee
- University of Pittsburgh Cancer Institute and Magee Women's Research Institute, Pittsburgh, PA 15213, United States
| | - J E Levine
- Wisconsin National Primate Research Center, Madison, WI 53715, United States
| | - R P Millar
- UCT/MRC Receptor Biology Unit, University of Cape Town, Cape Town, South Africa
| | - R J Nelson
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH 43210, United States
| | - M Porta
- Hospital del Mar Institute of Medical Research and School of Medicine, Universitat Autònoma de Barcelona, 080041 Barcelona, Spain
| | - M Poth
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States
| | - D M Power
- Department of Biosciences, Universidade do Algarve, 8005-139 Faro, Portugal
| | - G S Prins
- Department of Physiology and Biophysics, University of Illinois, Chicago, IL 60612, United States
| | - E C Ridgway
- Department of Medicine, University of Colorado School of Medicine, Denver, CO 80208, United States
| | - E F Rissman
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, VA 22908, United States
| | - J A Romijn
- Division of Medicine, Academic Medical Center, University of Amsterdam, 1012 WX Amsterdam, The Netherlands
| | - P E Sawchenko
- Laboratory of Neuronal Structure and Function, The Salk Institute, La Jolla, CA 92037, United States
| | - P D Sly
- Queensland Children's Medical Institute, University of Queensland, Royal Children's Hospital, Brisbane, Queensland 4000, Australia
| | - O Söder
- Karolinska Institutet at Karolinska University Hospital Solna, 171 76 Stockholm, Sweden
| | - H S Taylor
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT 06510, United States
| | - M Tena-Sempere
- Department of Cell Biology and Physiology, University of Córdoba, 14071 Córdoba, Spain
| | - H Vaudry
- Institut National de la Santé et de la Recherche Médicale U982, University of Rouen, 76821 Rouen, France
| | - K Wallen
- Department of Psychology and Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, United States
| | - Z Wang
- Department of Psychology and Neuroscience, Florida State University, Tallahassee, FL 32306, United States
| | - L Wartofsky
- Department of Medicine, Washington Hospital Center, Washington, DC 20010, United States
| | - C S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, United States
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15
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Watson CS, Jeng YJ, Bulayeva NN, Finnerty CC, Koong LY, Zivadinovic D, Alyea RA, Midoro-Horiuti T, Goldblum RM, Anastasio NC, Cunningham KA, Seitz PK, Smith TD. Multi-well plate immunoassays for measuring signaling protein activations/deactivations and membrane vs. intracellular receptor levels. Methods Mol Biol 2014; 1204:123-133. [PMID: 25182766 PMCID: PMC9159966 DOI: 10.1007/978-1-4939-1346-6_11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We developed fixed-cell multi-well plate immunoassays that increase the throughput and ease of quantification for questions formerly assessed by immunoblot scanning. The assays make use of the now abundant antibodies designed to recognize receptor subtypes and posttranslationally modified signaling proteins. By optimizing permeabilization and fixation conditions, mainly based on specific cell types, the assay can be adapted to the study of many different antigens of importance to hormonal and neurotransmitter signaling scenarios.
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Affiliation(s)
- Cheryl S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 0645 312 Basic Science Building, Galveston, TX, 77555, USA,
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Gore AC, Balthazart J, Bikle D, Carpenter DO, Crews D, Czernichow P, Diamanti-Kandarakis E, Dores RM, Grattan D, Hof PR, Hollenberg AN, Lange C, Lee AV, Levine JE, Millar RP, Nelson RJ, Porta M, Poth M, Power DM, Prins GS, Ridgway EC, Rissman EF, Romijn JA, Sawchenko PE, Sly PD, Söder O, Taylor HS, Tena-Sempere M, Vaudry H, Wallen K, Wang Z, Wartofsky L, Watson CS. Policy decisions on endocrine disruptors should be based on science across disciplines: a response to Dietrich et al. Eur J Endocrinol 2013; 169:E1-4. [PMID: 24057478 DOI: 10.1530/eje-13-0763] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- A C Gore
- Division of Pharmacology and Toxicology, The University of Texas, Austin, Texas 78712, USA
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17
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Gore AC, Balthazart J, Bikle D, Carpenter DO, Crews D, Czernichow P, Diamanti-Kandarakis E, Dores RM, Grattan D, Hof PR, Hollenberg AN, Lange C, Lee AV, Levine JE, Millar RP, Nelson RJ, Porta M, Poth M, Power DM, Prins GS, Ridgway EC, Rissman EF, Romijn JA, Sawchenko PE, Sly PD, Söder O, Taylor HS, Tena-Sempere M, Vaudry H, Wallen K, Wang Z, Wartofsky L, Watson CS. Policy decisions on endocrine disruptors should be based on science across disciplines: a response to Dietrich et al. Endocrinology 2013; 154:3957-60. [PMID: 24048095 PMCID: PMC5398595 DOI: 10.1210/en.2013-1854] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- A C Gore
- PhD, Editor-in-Chief, Endocrinology, Gustavus, Louise Pfeiffer Professor of Pharmacology, Toxicology, The University of Texas at Austin, Austin, Texas 78712.
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18
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Saraf MK, Jeng Y, Watson CS. R‐Equol‐induced non‐genomic estrogenic effects and interactions with estradiol signaling. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1167.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Manish Kumar Saraf
- Biochemistry and Molecular BiologyUniversity of Texas Medical BranchGalvestonTX
| | - Yow‐Jiun Jeng
- Biochemistry and Molecular BiologyUniversity of Texas Medical BranchGalvestonTX
| | - Cheryl S Watson
- Biochemistry and Molecular BiologyUniversity of Texas Medical BranchGalvestonTX
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Viñas R, Watson CS. Mixtures of xenoestrogens disrupt estradiol-induced non-genomic signaling and downstream functions in pituitary cells. Environ Health 2013; 12:26. [PMID: 23530988 PMCID: PMC3643824 DOI: 10.1186/1476-069x-12-26] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 02/28/2013] [Indexed: 05/18/2023]
Abstract
BACKGROUND Our study examines the effects of xenoestrogen mixtures on estradiol-induced non-genomic signaling and associated functional responses. Bisphenol-A, used to manufacture plastic consumer products, and nonylphenol, a surfactant, are estrogenic by a variety of assays, including altering many intracellular signaling pathways; bisphenol-S is now used as a bisphenol-A substitute. All three compounds contaminate the environment globally. We previously showed that bisphenol-S, bisphenol-A, and nonylphenol alone rapidly activated several kinases at very low concentrations in the GH3/B6/F10 rat pituitary cell line. METHODS For each assay we compared the response of individual xenoestrogens at environmentally relevant concentrations (10-15 -10-7 M), to their mixture effects on 10-9 M estradiol-induced responses. We used a medium-throughput plate immunoassay to quantify phosphorylations of extracellular signal-regulated kinases (ERKs) and c-Jun-N-terminal kinases (JNKs). Cell numbers were assessed by crystal violet assay to compare the proliferative effects. Apoptosis was assessed by measuring caspase 8 and 9 activities via the release of the fluorescent product 7-amino-4-trifluoromethylcoumarin. Prolactin release was measured by radio-immunoassay after a 1 min exposure to all individual and combinations of estrogens. RESULTS Individual xenoestrogens elicited phospho-activation of ERK in a non-monotonic dose- (fM-nM) and mostly oscillating time-dependent (2.5-60 min) manner. When multiple xenoestrogens were combined with nM estradiol, the physiologic estrogen's response was attenuated. Individual bisphenol compounds did not activate JNK, while nonylphenol did; however, the combination of two or three xenoestrogens with estradiol generated an enhanced non-monotonic JNK dose-response. Estradiol and all xenoestrogen compounds induced cell proliferation individually, while the mixtures of these compounds with estradiol suppressed proliferation below that of the vehicle control, suggesting a possible apoptotic response. Extrinsic caspase 8 activity was suppressed by estradiol, elevated by bisphenol S, and unaffected by mixtures. Intrinsic caspase 9 activity was inhibited by estradiol, and by xenoestrogen combinations (at 10-14 and 10-8 M). Mixtures of xenoestrogens impeded the estradiol-induced release of prolactin. CONCLUSIONS In mixtures expected to be found in contaminated environments, xenoestrogens can have dramatic disrupting effects on hormonal mechanisms of cell regulation and their downstream functional responses, altering cellular responses to physiologic estrogens.
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Affiliation(s)
- René Viñas
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555-0645, USA
| | - Cheryl S Watson
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555-0645, USA
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20
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Viñas R, Watson CS. Bisphenol S disrupts estradiol-induced nongenomic signaling in a rat pituitary cell line: effects on cell functions. Environ Health Perspect 2013; 121:352-8. [PMID: 23458715 PMCID: PMC3621186 DOI: 10.1289/ehp.1205826] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 12/13/2012] [Indexed: 05/02/2023]
Abstract
BACKGROUND Bisphenol A (BPA) is a well-known endocrine disruptor that imperfectly mimics the effects of physiologic estrogens via membrane-bound estrogen receptors (mERα, mERβ, and GPER/GPR30), thereby initiating nongenomic signaling. Bisphenol S (BPS) is an alternative to BPA in plastic consumer products and thermal paper. OBJECTIVE To characterize the nongenomic activities of BPS, we examined signaling pathways it evoked in GH3/B6/F10 rat pituitary cells alone and together with the physiologic estrogen estradiol (E2). Extracellular signal-regulated kinase (ERK)- and c-Jun-N-terminal kinase (JNK)-specific phosphorylations were examined for their correlation to three functional responses: proliferation, caspase activation, and prolactin (PRL) release. METHODS We detected ERK and JNK phosphorylations by fixed-cell immunoassays, identified the predominant mER initiating the signaling with selective inhibitors, estimated cell numbers by crystal violet assays, measured caspase activity by cleavage of fluorescent caspase substrates, and measured PRL release by radioimmunoassay. RESULTS BPS phosphoactivated ERK within 2.5 min in a nonmonotonic dose-dependent manner (10-15 to 10-7 M). When combined with 10-9 M E2, the physiologic estrogen's ERK response was attenuated. BPS could not activate JNK, but it greatly enhanced E2-induced JNK activity. BPS induced cell proliferation at low concentrations (femtomolar to nanomolar), similar to E2. Combinations of both estrogens reduced cell numbers below those of the vehicle control and also activated caspases. Earlier activation of caspase 8 versus caspase 9 demonstrated that BPS initiates apoptosis via the extrinsic pathway, consistent with activation via a membrane receptor. BPS also inhibited rapid (≤ 1 min) E2-induced PRL release. CONCLUSION BPS, once considered a safe substitute for BPA, disrupts membrane-initiated E2-induced cell signaling, leading to altered cell proliferation, cell death, and PRL release.
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Affiliation(s)
- René Viñas
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch Galveston, Texas 77555-0645, USA
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21
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Cunningham KA, Anastasio NC, Fox RG, Stutz SJ, Bubar MJ, Swinford SE, Watson CS, Gilbertson SR, Rice KC, Rosenzweig-Lipson S, Moeller FG. Synergism between a serotonin 5-HT2A receptor (5-HT2AR) antagonist and 5-HT2CR agonist suggests new pharmacotherapeutics for cocaine addiction. ACS Chem Neurosci 2013; 4:110-21. [PMID: 23336050 DOI: 10.1021/cn300072u] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Accepted: 08/11/2012] [Indexed: 11/30/2022] Open
Abstract
Relapse to cocaine dependence, even after extended abstinence, involves a number of liability factors including impulsivity (predisposition toward rapid, unplanned reactions to stimuli without regard to negative consequences) and cue reactivity (sensitivity to cues associated with cocaine-taking which can promote cocaine-seeking). These factors have been mechanistically linked to serotonin (5-hydroxytryptamine, 5-HT) signaling through the 5-HT(2A) receptor (5-HT(2A)R) and 5-HT(2C)R; either a selective 5-HT(2A)R antagonist or a 5-HT(2C)R agonist suppresses impulsivity and cocaine-seeking in preclinical models. We conducted proof-of-concept analyses to evaluate whether a combination of 5-HT(2A)R antagonist plus 5-HT(2C)R agonist would have synergistic effects over these liability factors for relapse as measured in a 1-choice serial reaction time task and cocaine self-administration/reinstatement assay. Combined administration of a dose of the selective 5-HT(2A)R antagonist M100907 plus the 5-HT(2C)R agonist WAY163909, each ineffective alone, synergistically suppressed cocaine-induced hyperactivity, inherent and cocaine-evoked impulsive action, as well as cue- and cocaine-primed reinstatement of cocaine-seeking behavior. The identification of synergism between a 5-HT(2A)R antagonist plus a 5-HT(2C)R agonist to attenuate these factors important in relapse indicates the promise of a bifunctional ligand as an anti-addiction pharmacotherapeutic, setting the stage to develop new ligands with improved efficacy, potency, selectivity, and in vivo profiles over the individual molecules.
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Affiliation(s)
| | | | | | | | | | | | | | - Scott R. Gilbertson
- Department of Chemistry, University of Houston, Houston, Texas, , United States
| | - Kenner C. Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, , United States
| | | | - F. Gerard Moeller
- Center for Neurobehavioral Research
on Addictions, Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center Houston,
Houston, Texas, , United States
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Viñas R, Jeng YJ, Watson CS. Non-genomic effects of xenoestrogen mixtures. Int J Environ Res Public Health 2012; 9:2694-714. [PMID: 23066391 PMCID: PMC3447581 DOI: 10.3390/ijerph9082694] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/09/2012] [Accepted: 07/17/2012] [Indexed: 12/13/2022]
Abstract
Xenoestrogens (XEs) are chemicals derived from a variety of natural and anthropogenic sources that can interfere with endogenous estrogens by either mimicking or blocking their responses via non-genomic and/or genomic signaling mechanisms. Disruption of estrogens' actions through the less-studied non-genomic pathway can alter such functional end points as cell proliferation, peptide hormone release, catecholamine transport, and apoptosis, among others. Studies of potentially adverse effects due to mixtures and to low doses of endocrine-disrupting chemicals have recently become more feasible, though few so far have included actions via the non-genomic pathway. Physiologic estrogens and XEs evoke non-monotonic dose responses, with different compounds having different patterns of actions dependent on concentration and time, making mixture assessments all the more challenging. In order to understand the spectrum of toxicities and their mechanisms, future work should focus on carefully studying individual and mixture components across a range of concentrations and cellular pathways in a variety of tissue types.
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Affiliation(s)
- René Viñas
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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23
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Watson CS, Jeng YJ, Hu G, Wozniak A, Bulayeva N, Guptarak J. Estrogen- and xenoestrogen-induced ERK signaling in pituitary tumor cells involves estrogen receptor-α interactions with G protein-αi and caveolin I. Steroids 2012; 77:424-32. [PMID: 22230296 PMCID: PMC3304022 DOI: 10.1016/j.steroids.2011.12.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 12/21/2011] [Accepted: 12/22/2011] [Indexed: 12/16/2022]
Abstract
UNLABELLED Multiple physiologic estrogens (estradiol, estriol, and estrone), as well as xenoestrogenic compounds (including alkylphenols and bisphenol A), can act via nongenomic signaling initiated by liganding of the plasma membrane estrogen receptor-α (mERα). We examined heterotrimeric G protein involvement leading to extracellular-regulated kinase (ERK) activation in GH3/B6/F10 rat anterior pituitary tumor cells that express abundant mERα, and smaller amounts of mERβ and GPR30. A combination of microarrays, immunoblots, and quantitative immunoassays demonstrated the expression of members of all α, β, and γ G protein classes in these cells. Use of selective inhibitors showed that the G(αi) subtype was the primary initiator of downstream ERK signaling. Using antibodies against the GTP-bound form of G(α) protein subtypes i and s, we showed that xenoestrogens (bisphenol A, nonylphenol) activated G(αi) at 15-30s; all alkylphenols examined subsequently suppressed activation by 5min. GTP-activation of G(αi) for all estrogens was enhanced by irreversible cumulative binding to GTPγS. In contrast, G(αs) was neither activated nor deactivated by these treatments with estrogens. ERα and G(αi) co-localized outside nuclei and could be immuno-captured together. Interactions of ERα with G(αi) and caveolin I were demonstrated by epitope proximity ligation assays. An ERα/β antagonist (ICI182780) and a selective disruptor of caveolar structures (nystatin) blocked estrogen-induced ERK activation. CONCLUSIONS Xenoestrogens, like physiologic estrogens, can evoke downstream kinase signaling involving selective interactions of ERα with G(αi) and caveolin I, but with some different characteristics, which could explain their disruptive actions.
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Affiliation(s)
- Cheryl S Watson
- Dept. of Biochemistry & Molecular Biology, Univ. of Texas Medical Branch, Galveston, TX 77555-0645, USA.
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24
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Seitz PK, Bremer NM, McGinnis AG, Cunningham KA, Watson CS. Quantitative changes in intracellular calcium and extracellular-regulated kinase activation measured in parallel in CHO cells stably expressing serotonin (5-HT) 5-HT2A or 5-HT2C receptors. BMC Neurosci 2012; 13:25. [PMID: 22397586 PMCID: PMC3380724 DOI: 10.1186/1471-2202-13-25] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 03/07/2012] [Indexed: 01/14/2023] Open
Abstract
Background The serotonin (5-HT) 2A and 2C receptors (5-HT2AR and 5-HT2CR) are involved in a wide range of physiological and behavioral processes in the mammalian central and peripheral nervous systems. These receptors share a high degree of homology, have overlapping pharmacological profiles, and utilize many of the same and richly diverse second messenger signaling systems. We have developed quantitative assays for cells stably expressing these two receptors involving minimal cell sample manipulations that dramatically improve parallel assessments of two signaling responses: intracellular calcium (Cai++) changes and activation (phosphorylation) of downstream kinases. Such profiles are needed to begin to understand the simultaneous contributions from the multiplicity of signaling cascades likely to be initiated by serotonergic ligands. Results We optimized the Cai++ assay for stable cell lines expressing either 5-HT2AR or 5-HT2CR (including dye use and measurement parameters; cell density and serum requirements). We adapted a quantitative 96-well plate immunoassay for pERK in the same cell lines. Similar cell density optima and time courses were observed for 5-HT2AR- and 5-HT2CR-expressing cells in generating both types of signaling. Both cell lines also require serum-free preincubation for maximal agonist responses in the pERK assay. However, 5-HT2AR-expressing cells showed significant release of Cai++ in response to 5-HT stimulation even when preincubated in serum-replete medium, while the response was completely eliminated by serum in 5-HT2CR-expressing cells. Response to another serotonergic ligand (DOI) was eliminated by serum-replete preincubation in both cells lines. Conclusions These data expand our knowledge of differences in ligand-stimulated signaling cascades between 5-HT2AR and 5-HT2CR. Our parallel assays can be applied to other cell and receptor systems for monitoring and dissecting concurrent signaling responses.
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Affiliation(s)
- Patricia K Seitz
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555, USA
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25
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Shashack MJ, Cunningham KA, Seitz PK, McGinnis A, Smith TD, Watson CS, Gilbertson SR. Synthesis and evaluation of dimeric derivatives of 5-HT(2A) receptor (5-HT(2A)R) antagonist M-100907. ACS Chem Neurosci 2011; 2:640-644. [PMID: 22247793 DOI: 10.1021/cn200077q] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
It is now well accepted that at least some serotonin receptors exist in dimeric and oligmeric forms. The linking of receptor ligands has been shown to have potential in the development of selective agonists and antagonists for traditionally refractive receptors. Here we report the development of a dimeric version of the known 5-HT(2A)R antagonist, M-100907. Derivatives of M-100907 were synthesized to determine an appropriate site for the linker connection. Then, homodimers with polyether linkers of different lengths were functionally tested in a bioassay to determine the optimal linker length. Attachment at the catechol of M-100907 with linkers between 12 and 18 atoms in length proved to be optimal.
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Affiliation(s)
- Matthew J. Shashack
- Department of Pharmacology and Toxicology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0615, United States
| | - Kathryn A. Cunningham
- Department of Pharmacology and Toxicology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0615, United States
| | - Patricia K. Seitz
- Department of Pharmacology and Toxicology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0615, United States
| | - Andrew McGinnis
- Department of Pharmacology and Toxicology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0615, United States
| | - Thressa D. Smith
- Department of Pharmacology and Toxicology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0615, United States
| | - Cheryl S. Watson
- Department of Biochemistry and Molecular Biology, Center for Addiction Research, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-0647, United States
| | - Scott R. Gilbertson
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
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Watson CS, Jeng YJ, Guptarak J. Endocrine disruption via estrogen receptors that participate in nongenomic signaling pathways. J Steroid Biochem Mol Biol 2011; 127:44-50. [PMID: 21300151 PMCID: PMC3106143 DOI: 10.1016/j.jsbmb.2011.01.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 01/27/2011] [Accepted: 01/30/2011] [Indexed: 12/21/2022]
Abstract
When inappropriate (non-physiologic) estrogens affect organisms at critical times of estrogen sensitivity, disruption of normal endocrine functions can result. Non-physiologic estrogen mimetics (environmental, dietary, and pharmaceutical) can signal rapidly and potently via the membrane versions of estrogen receptors, as can physiologic estrogens. Both physiologic and non-physiologic estrogens activate multiple signaling pathways, leading to altered cellular functions (e.g. peptide release, cell proliferation or death, transport). Xenoestrogens' mimicry of physiologic estrogens is imperfect. When superimposed, xenoestrogens can alter endogenous estrogens' signaling and thereby disrupt normal signaling pathways, leading to malfunctions in many tissue types. Though these xenoestrogen actions occur rapidly via nongenomic signaling pathways, they can be sustained with continuing ligand stimulation, combinations of ligands, and signaling that perpetuates downstream, eventually also impinging on genomic regulation by controlling the activation state of transcription factors. Because via these pathways estrogens and xenoestrogens cause nonmonotonic stimulation patterns, they must be carefully tested for activity and toxicity over wide dose ranges. Nongenomic actions of xenoestrogens in combination with each other, and with physiologic estrogens, are still largely unexplored from these mechanistic perspectives.
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Affiliation(s)
- Cheryl S. Watson
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston TX 77555-0645, USA
| | - Yow-Juin Jeng
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston TX 77555-0645, USA
| | - Jutatip Guptarak
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston TX 77555-0645, USA
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Jeng YJ, Watson CS. Combinations of physiologic estrogens with xenoestrogens alter ERK phosphorylation profiles in rat pituitary cells. Environ Health Perspect 2011; 119:104-12. [PMID: 20870566 PMCID: PMC3018487 DOI: 10.1289/ehp.1002512] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 09/22/2010] [Indexed: 05/08/2023]
Abstract
BACKGROUND Estrogens are potent nongenomic phospho-activators of extracellular-signal-regulated kinases (ERKs). A major concern about the toxicity of xenoestrogens (XEs) is potential alteration of responses to physiologic estrogens when XEs are present simultaneously. OBJECTIVES We examined estrogen-induced ERK activation, comparing the abilities of structurally related XEs (alkylphenols and bisphenol A) to alter ERK responses induced by physiologic concentrations (1 nM) of estradiol (E2), estrone (E1), and estriol (E3). METHODS We quantified hormone/mimetic-induced ERK phosphorylations in the GH3/B6/F10 rat pituitary cell line using a plate immunoassay, comparing effects with those on cell proliferation and by estrogen receptor subtype-selective ligands. RESULTS Alone, these structurally related XEs activate ERKs in an oscillating temporal pattern similar (but not identical) to that with physiologic estrogens. The potency of all estrogens was similar (active between femtomolar and nanomolar concentrations). XEs potently disrupted physiologic estrogen signaling at low, environmentally relevant concentrations. Generally, XEs potentiated (at the lowest, subpicomolar concentrations) and attenuated (at the highest, picomolar to 100 nM concentrations) the actions of the physiologic estrogens. Some XEs showed pronounced nonmonotonic responses/inhibitions. The phosphorylated ERK and proliferative responses to receptor-selective ligands were only partially correlated. CONCLUSIONS XEs are both imperfect potent estrogens and endocrine disruptors; the more efficacious an XE, the more it disrupts actions of physiologic estrogens. This ability to disrupt physiologic estrogen signaling suggests that XEs may disturb normal functioning at life stages where actions of particular estrogens are important (e.g., development, reproductive cycling, pregnancy, menopause).
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Affiliation(s)
| | - Cheryl S. Watson
- Address correspondence to C.S. Watson, Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645 USA. Telephone/fax: (409) 772-2383. E-mail:
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Jeng YJ, Kochukov M, Watson CS. Combinations of physiologic estrogens with xenoestrogens alter calcium and kinase responses, prolactin release, and membrane estrogen receptor trafficking in rat pituitary cells. Environ Health 2010; 9:61. [PMID: 20950447 PMCID: PMC2967504 DOI: 10.1186/1476-069x-9-61] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Accepted: 10/15/2010] [Indexed: 05/18/2023]
Abstract
BACKGROUND Xenoestrogens such as alkylphenols and the structurally related plastic byproduct bisphenol A have recently been shown to act potently via nongenomic signaling pathways and the membrane version of estrogen receptor-α. Though the responses to these compounds are typically measured individually, they usually contaminate organisms that already have endogenous estrogens present. Therefore, we used quantitative medium-throughput screening assays to measure the effects of physiologic estrogens in combination with these xenoestrogens. METHODS We studied the effects of low concentrations of endogenous estrogens (estradiol, estriol, and estrone) at 10 pM (representing pre-development levels), and 1 nM (representing higher cycle-dependent and pregnancy levels) in combinations with the same levels of xenoestrogens in GH3/B6/F10 pituitary cells. These levels of xenoestrogens represent extremely low contamination levels. We monitored calcium entry into cells using Fura-2 fluorescence imaging of single cells. Prolactin release was measured by radio-immunoassay. Extracellular-regulated kinase (1 and 2) phospho-activations and the levels of three estrogen receptors in the cell membrane (ERα, ERβ, and GPER) were measured using a quantitative plate immunoassay of fixed cells either permeabilized or nonpermeabilized (respectively). RESULTS All xenoestrogens caused responses at these concentrations, and had disruptive effects on the actions of physiologic estrogens. Xenoestrogens reduced the % of cells that responded to estradiol via calcium channel opening. They also inhibited the activation (phosphorylation) of extracellular-regulated kinases at some concentrations. They either inhibited or enhanced rapid prolactin release, depending upon concentration. These latter two dose-responses were nonmonotonic, a characteristic of nongenomic estrogenic responses. CONCLUSIONS Responses mediated by endogenous estrogens representing different life stages are vulnerable to very low concentrations of these structurally related xenoestrogens. Because of their non-classical dose-responses, they must be studied in detail to pinpoint effective concentrations and the directions of response changes.
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Affiliation(s)
- Yow-Jiun Jeng
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Mikhail Kochukov
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Cheryl S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
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Watson CS, Alyea RA, Cunningham KA, Jeng YJ. Estrogens of multiple classes and their role in mental health disease mechanisms. Int J Womens Health 2010; 2:153-66. [PMID: 21072308 PMCID: PMC2971739 DOI: 10.2147/ijwh.s6907] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2010] [Indexed: 12/21/2022] Open
Abstract
Gender and sex hormones can influence a variety of mental health states, including mood, cognitive development and function, and vulnerability to neurodegenerative diseases and brain damage. Functions of neuronal cells may be altered by estrogens depending upon the availability of different physiological estrogenic ligands; these ligands and their effects vary with life stages, the genetic or postgenetic regulation of receptor levels in specific tissues, or the intercession of competing nonphysiological ligands (either intentional or unintentional, beneficial to health or not). Here we review evidence for how different estrogens (physiological and environmental/dietary), acting via different estrogen receptor subtypes residing in alternative subcellular locations, influence brain functions and behavior. We also discuss the families of receptors and transporters for monoamine neurotransmitters and how they may interact with the estrogenic signaling pathways.
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Anastasio NC, Lanfranco MF, Bubar MJ, Seitz PK, Stutz SJ, McGinnis AG, Watson CS, Cunningham KA. Serotonin 5-HT2C receptor protein expression is enriched in synaptosomal and post-synaptic compartments of rat cortex. J Neurochem 2010; 113:1504-15. [PMID: 20345755 PMCID: PMC2917206 DOI: 10.1111/j.1471-4159.2010.06694.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The action of serotonin (5-HT) at the 5-HT(2C) receptor (5-HT(2C)R) in cerebral cortex is emerging as a candidate modulator of neural processes that mediate core phenotypic facets of several psychiatric and neurological disorders. However, our understanding of the neurobiology of the cortical 5-HT(2C)R protein complex is currently limited. The goal of the present study was to explore the subcellular localization of the 5-HT(2C)R in synaptosomes and the post-synaptic density, an electron-dense thickening specialized for post-synaptic signaling and neuronal plasticity. Utilizing multiples tissues (brain, peripheral tissues), protein fractions (synaptosomal, post-synaptic density), and controls (peptide neutralization, 5-HT(2C)R stably-expressing cells), we established the selectivity of two commercially available 5-HT(2C)R antibodies and employed the antibodies in western blot and immunoprecipitation studies of prefrontal cortex (PFC) and motor cortex, two regions implicated in cognitive, emotional and motor dysfunction. For the first time, we demonstrated the expression of the 5-HT(2C)R in post-synaptic density-enriched fractions from both PFC and motor cortex. Co-immunoprecipitation studies revealed the presence of post-synaptic density-95 within the 5-HT(2C)R protein complex expressed in PFC and motor cortex. Taken together, these data support the hypothesis that the 5-HT(2C)R is localized within the post-synaptic thickening of synapses and is therefore positioned to directly modulate synaptic plasticity in cortical neurons.
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Affiliation(s)
- Noelle C. Anastasio
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Maria Fe Lanfranco
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Marcy J. Bubar
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Patricia K. Seitz
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Sonja J. Stutz
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Andrew G. McGinnis
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
| | - Cheryl S. Watson
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston TX 77555
| | - Kathryn A. Cunningham
- Center for Addiction Research, University of Texas Medical Branch, Galveston TX 77555
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston TX 77555
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Jeng YJ, Kochukov M, Nauduri D, Kaphalia BS, Watson CS. Subchronic exposure to phytoestrogens alone and in combination with diethylstilbestrol - pituitary tumor induction in Fischer 344 rats. Nutr Metab (Lond) 2010; 7:40. [PMID: 20459739 PMCID: PMC2881934 DOI: 10.1186/1743-7075-7-40] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 05/10/2010] [Indexed: 11/10/2022] Open
Abstract
Background Subchronic administration of the potent pharmaceutical estrogen diethylstilbestrol (DES) to female Fischer 344 (F344) rats induces growth of large, hemorrhagic pituitaries that progress to tumors. Phytoestrogens (dietary plant estrogens) are hypothesized to be potential tumor inhibitors in tissues prone to estrogen-induced cancers, and have been suggested as "safer" estrogen replacements. However, it is unknown if they might themselves establish or exacerbate the growth of estrogen-responsive cancers, such as in pituitary. Methods We implanted rats with silastic capsules containing 5 mg of four different phytoestrogens - either coumestrol, daidzein, genistein, or trans-resveratrol, in the presence or absence of DES. We examined pituitary and other organ weights, blood levels of prolactin (PRL) and growth hormone (GH), body weights, and pituitary tissue histology. Results Blood level measurements of the administered phytoestrogens confirmed successful exposure of the animals to high levels of these compounds. By themselves, no phytoestrogen increased pituitary weights or serum PRL levels after 10 weeks of treatment. DES, genistein, and resveratrol increased GH levels during this time. Phytoestrogens neither changed any wet organ weight (uterus, ovary, cervix, liver, and kidney) after 10 weeks of treatment, nor reversed the adverse effects of DES on pituitaries, GH and PRL levels, or body weight gain after 8 weeks of co-treatment. However, they did reverse the DES-induced weight increase on the ovary and cervix. Morphometric examination of pituitaries revealed that treatment with DES, either alone or in combination with phytoestrogens, caused gross structural changes that included decreases in tissue cell density, increases in vascularity, and multiple hemorrhagic areas. DES, especially in combination with phytoestrogens, caused the development of larger and more heterogeneous nuclear sizes in pituitary. Conclusions High levels of phytoestrogens by themselves did not cause pituitary precancerous growth or change weights of other estrogen-sensitive organs, though when combined with DES, they counteracted the growth effects of DES on reproductive organs. In the pituitary, phytoestrogens did not reverse the effects of DES, but they did increase the sizes and size heterogeneity of nuclei. Therefore, phytoestrogens may oppose some but not all estrogen-responsive tissue abnormalities caused by DES overstimulation, and appear to exacerbate DES-induced nuclear changes.
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Affiliation(s)
- Yow-Jiun Jeng
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA.
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vom Saal FS, Akingbemi BT, Belcher SM, Crain DA, Crews D, Guidice LC, Hunt PA, Leranth C, Myers JP, Nadal A, Olea N, Padmanabhan V, Rosenfeld CS, Schneyer A, Schoenfelder G, Sonnenschein C, Soto AM, Stahlhut RW, Swan SH, Vandenberg LN, Wang HS, Watson CS, Welshons WV, Zoeller RT. Flawed Experimental Design Reveals the Need for Guidelines Requiring Appropriate Positive Controls in Endocrine Disruption Research. Toxicol Sci 2010; 115:612-3. [DOI: 10.1093/toxsci/kfq048] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Midoro-Horiuti T, Tiwari R, Watson CS, Goldblum RM. Maternal bisphenol a exposure promotes the development of experimental asthma in mouse pups. Environ Health Perspect 2010; 118:273-7. [PMID: 20123615 PMCID: PMC2831929 DOI: 10.1289/ehp.0901259] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 10/05/2009] [Indexed: 05/18/2023]
Abstract
BACKGROUND We recently reported that various environmental estrogens induce mast cell degranulation and enhance IgE-mediated release of allergic mediators in vitro. OBJECTIVES We hypothesized that environmental estrogens would enhance allergic sensitization as well as bronchial inflammation and responsiveness. To test this hypothesis, we exposed fetal and neonatal mice to the common environmental estrogen bisphenol A (BPA) via maternal loading and assessed the pups' response to allergic sensitization and bronchial challenge. METHODS Female BALB/c mice received 10 microg/mL BPA in their drinking water from 1 week before impregnation to the end of the study. Neonatal mice were given a single 5 microg intraperitoneal dose of ovalbumin (OVA) with aluminum hydroxide on postnatal day 4 and 3% OVA by nebulization for 10 min on days 13, 14, and 15. Forty-eight hours after the last nebulization, we assessed serum IgE antibodies to OVA by enzyme-linked immunosorbent assay (ELISA) and airway inflammation and hyperresponsiveness by enumerating eosinophils in bronchoalveolar lavage fluid, whole-body barometric plethysmography, and a forced oscillation technique. RESULTS Neonates from BPA-exposed mothers responded to this "suboptimal" sensitization with higher serum IgE anti-OVA concentrations compared with those from unexposed mothers (p < 0.05), and eosinophilic inflammation in their airways was significantly greater. Airway responsiveness of the OVA-sensitized neonates from BPA-treated mothers was enhanced compared with those from unexposed mothers (p < 0.05). CONCLUSIONS Perinatal exposure to BPA enhances allergic sensitization and bronchial inflammation and responsiveness in a susceptible animal model of asthma.
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Affiliation(s)
- Terumi Midoro-Horiuti
- Department of Pediatrics, Child Health Research Center and
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
- Address correspondence to T. Midoro-Horiuti, Child Health Research Center, Children’s Hospital Room 2.300, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366 USA. Telephone: (409) 772-3832. Fax: (409) 772-1761. E-mail:
| | - Ruby Tiwari
- Department of Pediatrics, Child Health Research Center and
| | - Cheryl S. Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Randall M. Goldblum
- Department of Pediatrics, Child Health Research Center and
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
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Abstract
Xenoestrogens can affect the healthy functioning of a variety of tissues by acting as potent estrogens via nongenomic signaling pathways or by interfering with those actions of multiple physiological estrogens. Collectively, our and other studies have compared a wide range of estrogenic compounds, including some closely structurally related subgroups. The estrogens that have been studied include environmental contaminants of different subclasses, dietary estrogens, and several prominent physiological metabolites. By comparing the nongenomic signaling and functional responses to these compounds, we have begun to address the structural requirements for their actions through membrane estrogen receptors in the pituitary, in comparison to other tissues, and to gain insights into their typical non-monotonic dose-response behavior. Their multiple inputs into cellular signaling begin processes that eventually integrate at the level of mitogen-activated protein kinase activities to coordinately regulate broad cellular destinies, such as proliferation, apoptosis, or differentiation.
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Affiliation(s)
- Cheryl S Watson
- Biochemistry & Molecular Biology Department, University of Texas Medical Branch, Galveston, Texas 77555-0645, USA.
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Jeng YJ, Watson CS. Proliferative and anti-proliferative effects of dietary levels of phytoestrogens in rat pituitary GH3/B6/F10 cells - the involvement of rapidly activated kinases and caspases. BMC Cancer 2009; 9:334. [PMID: 19765307 PMCID: PMC2755011 DOI: 10.1186/1471-2407-9-334] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Accepted: 09/18/2009] [Indexed: 12/18/2022] Open
Abstract
Background Phytoestogens are a group of lipophillic plant compounds that can have estrogenic effects in animals; both tumorigenic and anti-tumorigenic effects have been reported. Prolactin-secreting adenomas are the most prevalent form of pituitary tumors in humans and have been linked to estrogen exposures. We examined the proliferative effects of phytoestrogens on a rat pituitary tumor cell line, GH3/B6/F10, originally subcloned from GH3 cells based on its ability to express high levels of the membrane estrogen receptor-α. Methods We measured the proliferative effects of these phytoestrogens using crystal violet staining, the activation of several mitogen-activated protein kinases (MAPKs) and their downstream targets via a quantitative plate immunoassay, and caspase enzymatic activities. Results Four phytoestrogens (coumestrol, daidzein, genistein, and trans-resveratrol) were studied over wide concentration ranges. Except trans-resveratrol, all phytoestrogens increased GH3/B6/F10 cell proliferation at some concentration relevant to dietary levels. All four phytoestrogens attenuated the proliferative effects of estradiol when administered simultaneously. All phytoestrogens elicited MAPK and downstream target activations, but with time course patterns that often differed from that of estradiol and each other. Using selective antagonists, we determined that MAPKs play a role in the ability of these phytoestrogens to elicit these responses. In addition, except for trans-resveratrol, a serum removal-induced extrinsic apoptotic pathway was blocked by these phytoestrogens. Conclusion Phytoestrogens can block physiological estrogen-induced tumor cell growth in vitro and can also stimulate growth at high dietary concentrations in the absence of endogenous estrogens; these actions are correlated with slightly different signaling response patterns. Consumption of these compounds should be considered in strategies to control endocrine tumor cell growth, such as in the pituitary.
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Affiliation(s)
- Yow-Jiun Jeng
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA.
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Abstract
Background Neurological diseases and neuropsychiatric disorders that vary depending on female life stages suggest that sex hormones may influence the function of neurotransmitter regulatory machinery such as the dopamine transporter (DAT). Results In this study we tested the rapid nongenomic effects of several physiological estrogens [estradiol (E2), estrone (E1), and estriol (E3)] on dopamine efflux via the DAT in a non-transfected, NGF-differentiated, rat pheochromocytoma (PC12) cell model that expresses membrane estrogen receptors (ERs) α, β, and GPR30. We examined kinase, ionic, and physical interaction mechanisms involved in estrogenic regulation of the DAT function. E2-mediated dopamine efflux is DAT-specific and not dependent on extracellular Ca2+-mediated exocytotic release from vesicular monoamine transporter vesicles (VMATs). Using kinase inhibitors we also showed that E2-mediated dopamine efflux is dependent on protein kinase C and MEK activation, but not on PI3K or protein kinase A. In plasma membrane there are ligand-independent associations of ERα and ERβ (but not GPR30) with DAT. Conditions which cause efflux (a 9 min 10-9 M E2 treatment) cause trafficking of ERα (stimulatory) to the plasma membrane and trafficking of ERβ (inhibitory) away from the plasma membrane. In contrast, E1 and E3 can inhibit efflux with a nonmonotonic dose pattern, and cause DAT to leave the plasma membrane. Conclusion Such mechanisms explain how gender biases in some DAT-dependent diseases can occur.
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Affiliation(s)
- Rebecca A Alyea
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0645, USA.
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Kochukov MY, Jeng YJ, Watson CS. Alkylphenol xenoestrogens with varying carbon chain lengths differentially and potently activate signaling and functional responses in GH3/B6/F10 somatomammotropes. Environ Health Perspect 2009; 117:723-30. [PMID: 19479013 PMCID: PMC2685833 DOI: 10.1289/ehp.0800182] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 12/31/2008] [Indexed: 05/02/2023]
Abstract
BACKGROUND Alkylphenols varying in their side-chain lengths [ethyl-, propyl-, octyl-, and nonylphenol (EP, PP, OP, and NP, respectively)] and bisphenol A (BPA) represent a large group of structurally related xenoestrogens that have endocrine-disruptive effects. Their rapid nongenomic effects that depend on structure for cell signaling and resulting functions are unknown. OBJECTIVES We compared nongenomic estrogenic activities of alkylphenols with BPA and 17beta-estradiol (E(2)) in membrane estrogen receptor-alpha-enriched GH3/B6/F10 pituitary tumor cells. These actions included calcium (Ca) signaling, prolactin (PRL) release, extracellular-regulated kinase (ERK) phosphorylation, and cell proliferation. METHODS We imaged Ca using fura-2, measured PRL release via radioimmunoassay, detected ERK phosphorylation by fixed cell immunoassay, and estimated cell number using the crystal violet assay. RESULTS All compounds caused increases in Ca oscillation frequency and intracellular Ca volume at 100 fM to 1 nM concentrations, although long-chain alkylphenols were most effective. All estrogens caused rapid PRL release at concentrations as low as 1 fM to 10 pM; the potency of EP, PP, and NP exceeded that of E(2). All compounds at 1 nM produced similar increases in ERK phosphorylation, causing rapid peaks at 2.5-5 min, followed by inactivation and additional 60-min peaks (except for BPA). Dose-response patterns of ERK activation at 5 min were similar for E2, BPA, and PP, whereas EP caused larger effects. Only E2 and NP increased cell number. Some rapid estrogenic responses showed correlations with the hydrophobicity of estrogenic molecules; the more hydrophobic OP and NP were superior at Ca and cell proliferation responses, whereas the less hydrophobic EP and PP were better at ERK activations. CONCLUSIONS Alkylphenols are potent estrogens in evoking these nongenomic responses contributing to complex functions; their hydrophobicity can largely predict these behaviors.
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Affiliation(s)
| | | | - Cheryl S. Watson
- Address correspondence to C.S. Watson, Biochemistry and Molecular Biology Dept., University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645 USA. Telephone or fax: (409) 772-2382. E-mail:
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Alyea RA, Watson CS. Differential regulation of dopamine transporter function and location by low concentrations of environmental estrogens and 17beta-estradiol. Environ Health Perspect 2009; 117:778-83. [PMID: 19479021 PMCID: PMC2685841 DOI: 10.1289/ehp.0800026] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Accepted: 01/05/2009] [Indexed: 05/04/2023]
Abstract
BACKGROUND The effects of 17beta-estradiol (E2) and xenoestrogens (XEs) on dopamine transport may have important implications for the increased incidence of neurologic disorders, especially in women during life stages characterized by frequent hormonal fluctuations. OBJECTIVE We examined low concentrations of XEs [dieldrin, endosulfan, o', p'-dichlorodiphenyl-ethylene (DDE), nonylphenol (NP), and bisphenol A (BPA)] for nongenomic actions via action of membrane estrogen receptors (ERs). METHODS We measured activity of the dopamine transporter (DAT) by the efflux of 3H-dopamine in nontransfected nerve growth factor-differentiated PC12 rat pheochromocytoma cells expressing membrane DAT, ER-alpha, ER-beta, and G-protein-coupled receptor 30. We used a plate immunoassay to monitor trafficking of these proteins. RESULTS All compounds at 1 nM either caused efflux or inhibited efflux, or both; each compound evoked a distinct oscillatory pattern. At optimal times for each effect, we examined different concentrations of XEs. All XEs were active at some concentration < 10 nM, and dose responses were all nonmonotonic. For example, 10(-14) to 10(-11) M DDE caused significant efflux inhibition, whereas NP and BPA enhanced or inhibited efflux at several concentrations. We also measured the effects of E2/XE combinations; DDE potentiated E(2)-mediated dopamine efflux, whereas BPA inhibited it. In E2-induced efflux, 15% more ER-alpha trafficked to the membrane, whereas ER-beta waned; during BPA-induced efflux, 20% more DAT was trafficked to the plasma membrane. CONCLUSIONS Low levels of environmental estrogen contaminants acting as endocrine disruptors via membrane ERs can alter dopamine efflux temporal patterning and the trafficking of DAT and membrane ERs, providing a cellular mechanism that could explain the disruption of physiologic neurotransmitter function.
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Affiliation(s)
- Rebecca A. Alyea
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Cheryl S. Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
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Jeng YJ, Kochukov MY, Watson CS. Membrane estrogen receptor-alpha-mediated nongenomic actions of phytoestrogens in GH3/B6/F10 pituitary tumor cells. J Mol Signal 2009; 4:2. [PMID: 19400946 PMCID: PMC2679742 DOI: 10.1186/1750-2187-4-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2009] [Accepted: 04/28/2009] [Indexed: 01/08/2023] Open
Abstract
Background Estradiol (E2) mediates various intracellular signaling cascades from the plasma membrane via several estrogen receptors (ERs). The pituitary is an estrogen-responsive tissue, and we have previously reported that E2 can activate mitogen-activated protein kinases (MAPKs) such as ERK1/2 and JNK1/2/3 in the membrane ERα (mERα)-enriched GH3/B6/F10 rat pituitary tumor cell line. Phytoestrogens are compounds found in plants and foods such as soybeans, alfalfa sprouts, and red grapes. They are structurally similar to E2 and share a similar mechanism of action through their binding to ERs. Phytoestrogens bind to nuclear ERs with a much lower affinity and therefore are less potent in mediating genomic responses. However, little is known about their ability to act via mERs to mediate nongenomic effects. Methods To investigate the activation of different nongenomic pathways, and determine the involvement of mERα, we measured prolactin (PRL) release by radio-immunoassay, MAPK activations (ERK1/2 and JNK1/2/3) via a quantitative plate immunoassay, and intracellular [Ca2+] by Fura-2 fluorescence imaging in cells treated with E2 or four different phytoestrogens (coumestrol, daidzein, genistein, and trans-resveratrol). Results Coumesterol and daidzein increased PRL release similar to E2 in GH3/B6/F10 cells, while genistein and trans-resveratrol had no effect. All of these compounds except genistein activated ERK1/2 signaling at 1–10 picomolar concentrations; JNK 1/2/3 was activated by all compounds at a 100 nanomolar concentration. All compounds also caused rapid Ca2+ uptake, though in unique dose-dependent Ca2+ response patterns for several aspects of this response. A subclone of GH3 cells expressing low levels of mERα (GH3/B6/D9) did not respond to any phytoestrogen treatments for any of these responses, suggesting that these nongenomic effects were mediated via mERα. Conclusion Phytoestrogens were much more potent in mediating these nongenomic responses (activation of MAPKs, PRL release, and increased intracellular [Ca2+]) via mERα than was previously reported for genomic responses. The unique non-monotonic dose responses and variant signaling patterns caused by E2 and all tested phytoestrogens suggest that complex and multiple signaling pathways or binding partners could be involved. By activating these different nongenomic signaling pathways, phytoestrogens could have significant physiological consequences for pituitary cell functions.
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Affiliation(s)
- Yow-Jiun Jeng
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA.
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Myers JP, vom Saal FS, Akingbemi BT, Arizono K, Belcher S, Colborn T, Chahoud I, Crain DA, Farabollini F, Guillette LJ, Hassold T, Ho SM, Hunt PA, Iguchi T, Jobling S, Kanno J, Laufer H, Marcus M, McLachlan JA, Nadal A, Oehlmann J, Olea N, Palanza P, Parmigiani S, Rubin BS, Schoenfelder G, Sonnenschein C, Soto AM, Talsness CE, Taylor JA, Vandenberg LN, Vandenbergh JG, Vogel S, Watson CS, Welshons WV, Zoeller RT. Why public health agencies cannot depend on good laboratory practices as a criterion for selecting data: the case of bisphenol A. Environ Health Perspect 2009; 117:309-15. [PMID: 19337501 PMCID: PMC2661896 DOI: 10.1289/ehp.0800173] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Accepted: 10/22/2008] [Indexed: 05/02/2023]
Abstract
BACKGROUND In their safety evaluations of bisphenol A (BPA), the U.S. Food and Drug Administration (FDA) and a counterpart in Europe, the European Food Safety Authority (EFSA), have given special prominence to two industry-funded studies that adhered to standards defined by Good Laboratory Practices (GLP). These same agencies have given much less weight in risk assessments to a large number of independently replicated non-GLP studies conducted with government funding by the leading experts in various fields of science from around the world. OBJECTIVES We reviewed differences between industry-funded GLP studies of BPA conducted by commercial laboratories for regulatory purposes and non-GLP studies conducted in academic and government laboratories to identify hazards and molecular mechanisms mediating adverse effects. We examined the methods and results in the GLP studies that were pivotal in the draft decision of the U.S. FDA declaring BPA safe in relation to findings from studies that were competitive for U.S. National Institutes of Health (NIH) funding, peer-reviewed for publication in leading journals, subject to independent replication, but rejected by the U.S. FDA for regulatory purposes. DISCUSSION Although the U.S. FDA and EFSA have deemed two industry-funded GLP studies of BPA to be superior to hundreds of studies funded by the U.S. NIH and NIH counterparts in other countries, the GLP studies on which the agencies based their decisions have serious conceptual and methodologic flaws. In addition, the U.S. FDA and EFSA have mistakenly assumed that GLP yields valid and reliable scientific findings (i.e., "good science"). Their rationale for favoring GLP studies over hundreds of publically funded studies ignores the central factor in determining the reliability and validity of scientific findings, namely, independent replication, and use of the most appropriate and sensitive state-of-the-art assays, neither of which is an expectation of industry-funded GLP research. CONCLUSIONS Public health decisions should be based on studies using appropriate protocols with appropriate controls and the most sensitive assays, not GLP. Relevant NIH-funded research using state-of-the-art techniques should play a prominent role in safety evaluations of chemicals.
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Watson CS, Jeng YJ, Kochukov MY. Nongenomic actions of estradiol compared with estrone and estriol in pituitary tumor cell signaling and proliferation. FASEB J 2008; 22:3328-36. [PMID: 18541692 DOI: 10.1096/fj.08-107672] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Physiological estrogens, including estrone (E(1)), estradiol (E(2)), and estriol (E(3)), fluctuate with life stage, suggesting specific roles for them in biological and disease processes. We compared their nongenomic signaling and functional actions in GH3/B6/F10 rat pituitary tumor cells. All hormones caused prolactin release at 1 min; the lowest effective concentrations were 10(-11) M E(2), 10(-10) M E(1), and 10(-7) M E(3). All estrogens increased the oscillation frequency of calcium (Ca) spikes, with the same time delay (approximately 200 s) at all levels (10(-15) to 10(-9) M). At some concentrations, E(1) and E(3) provoked more Ca-responding cells than E(2). The amplitude and volume of Ca peaks were elevated by all hormones at > or = 10(-15) M. All hormones caused cell proliferation, with the lowest effective concentrations of E(2) (10(-15) M) > E(1) (10(-12) M) > E(3) (10(-10) M); E(2) caused higher maximal cell numbers at most concentrations. All estrogens caused oscillating extracellular-regulated kinase (ERK) activations, with relative potencies of E(1) and E(2) > E(3). All estrogens were ineffective in activation of ERKs or causing proliferation in a subline expressing low levels of membrane estrogen receptor-alpha. Dose-response patterns were frequently nonmonotonic. Therefore, the hormones E(1) and E(3), which have been designated "weak" estrogens in genomic actions, are strong estrogens in the nongenomic signaling pathways and functional responses in the pituitary.
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Affiliation(s)
- Cheryl S Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0645, USA
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Alyea RA, Laurence SE, Kim SH, Katzenellenbogen BS, Katzenellenbogen JA, Watson CS. The roles of membrane estrogen receptor subtypes in modulating dopamine transporters in PC-12 cells. J Neurochem 2008; 106:1525-33. [PMID: 18489713 DOI: 10.1111/j.1471-4159.2008.05491.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The effects of 17beta-estradiol (E(2)) on dopamine (DA) transport could explain gender and life-stage differences in the incidence of some neurological disorders. We tested the effects of E(2) at physiological concentrations on DA efflux in nerve growth factor-differentiated rat pheochromocytoma cells that express estrogen receptors (ER) alpha, ERbeta, and G-protein coupled receptor 30 (GPR30), and DA transporter (DAT). DAT efflux was determined as the transporter-specific loss of (3)H-DA from pre-loaded cells; a 9-15 min 10(-9 )M E(2) treatment caused maximal DA efflux. Such rapid estrogenic action suggests a non-genomic response, and an E(2)-dendrimer conjugate (limited to non-nuclear actions) caused DA efflux within 5 min. Efflux dose-responses for E(2) were non-monotonic, also characteristic of non-genomic estrogenic actions. ERalpha siRNA knockdown abolished E(2)-mediated DA efflux, while ERbeta knockdown did not, and GPR30 knockdown increased E(2)-mediated DA efflux (suggesting GPR30 is inhibitory). Use of ER-selective agonists/antagonists demonstrated that ERalpha is the predominant mediator of E(2)-mediated DA efflux, with inhibitory contributions from GPR30 and ERbeta. E(2) also caused trafficking of ERalpha to the plasma membrane, trafficking of ERbeta away from the plasma membrane, and unchanged membrane GPR30 levels. Therefore, ERalpha is largely responsible for non-genomic estrogenic effects on DAT activity.
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Affiliation(s)
- Rebecca A Alyea
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
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Affiliation(s)
- Kathryn A. Cunningham
- Departments of *Pharmacology and Toxicology and
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-1031
| | - Cheryl S. Watson
- Biochemistry and Molecular Biology
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-1031
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Watson CS, Alyea RA, Jeng YJ, Kochukov MY. Nongenomic actions of low concentration estrogens and xenoestrogens on multiple tissues. Mol Cell Endocrinol 2007; 274:1-7. [PMID: 17601655 PMCID: PMC1986712 DOI: 10.1016/j.mce.2007.05.011] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Accepted: 05/17/2007] [Indexed: 10/23/2022]
Abstract
Nongenomic estrogenic mechanisms offer an opportunity to explain the conundrum of environmental estrogen and plant estrogen effects on cells and animals at the very low concentrations which are prevalent in our environments and diets. Heretofore the actions of these compounds have not been adequately accounted for by laboratory tests utilizing assays for actions only via the genomic pathway of steroid action and the nuclear forms of estrogen receptor alpha and beta. Membrane versions of these receptors, and the newly described GPR30 (7TMER) receptor protein provide explanations for the more potent actions of xenoestrogens. The effects of estrogens on many tissues demand a comprehensive assessment of the receptors, receptor levels, and mechanisms that might be involved, to determine which of these estrogen mimetic compounds are harmful and which might even be used therapeutically, depending upon the life stage at which we are exposed to them.
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Affiliation(s)
- C S Watson
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0645, USA.
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vom Saal FS, Akingbemi BT, Belcher SM, Birnbaum LS, Crain DA, Eriksen M, Farabollini F, Guillette LJ, Hauser R, Heindel JJ, Ho SM, Hunt PA, Iguchi T, Jobling S, Kanno J, Keri RA, Knudsen KE, Laufer H, LeBlanc GA, Marcus M, McLachlan JA, Myers JP, Nadal A, Newbold RR, Olea N, Prins GS, Richter CA, Rubin BS, Sonnenschein C, Soto AM, Talsness CE, Vandenbergh JG, Vandenberg LN, Walser-Kuntz DR, Watson CS, Welshons WV, Wetherill Y, Zoeller RT. Chapel Hill bisphenol A expert panel consensus statement: integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure. Reprod Toxicol 2007; 24:131-8. [PMID: 17768031 PMCID: PMC2967230 DOI: 10.1016/j.reprotox.2007.07.005] [Citation(s) in RCA: 544] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 07/11/2007] [Accepted: 07/20/2007] [Indexed: 11/18/2022]
Affiliation(s)
| | - Benson T. Akingbemi
- Department of Anatomy, Physiology and Pharmacology, Auburn University, Auburn, AL 36849, United States
| | - Scott M. Belcher
- Department of Pharmacology and Cell Biophysics, Center for Environmental Genetics, University of Cincinnati, Cincinnati, OH 45267, United States
| | - Linda S. Birnbaum
- U.S. Environmental Protection Agency, Research Triangle Park, NC 27709, United States
| | - D. Andrew Crain
- Biology Department, Maryville College, Maryville, TN 37804, United States
| | - Marcus Eriksen
- Algalita Marine Research Foundation, Los Angeles, CA 90034, United States
| | | | - Louis J. Guillette
- Department of Zoology, University of Florida, Gainesville, FL 32611, United States
| | - Russ Hauser
- Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, United States
| | - Jerrold J. Heindel
- Division of Extramural Research and Training, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, United States
| | - Shuk-Mei Ho
- Department of Environmental Health, University of Cincinnati Medical School, Cincinnati, OH 45267, United States
| | - Patricia A. Hunt
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164, United States
| | - Taisen Iguchi
- National Institutes of Natural Science, Okazaki Institute For Integrative Bioscience Bioenvironmental Science, Okazaki, Aichi 444-8787, Japan
| | - Susan Jobling
- Department of Biological Sciences, Brunel University, Uxbridge, Middlesex, UK
| | - Jun Kanno
- Division of Cellular & Molecular Toxicology, National Institute of Health Sciences, Tokyo 158-8501, Japan
| | - Ruth A. Keri
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, United States
| | - Karen E. Knudsen
- Department of Cell and Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, United States
| | - Hans Laufer
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States
| | - Gerald A. LeBlanc
- Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695, United States
| | - Michele Marcus
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - John A. McLachlan
- Center for Bioenvironmental Research, Tulane and Xavier Universities, New Orleans, LA 70112, United States
| | | | - Angel Nadal
- Instituto de Bioingeniería, Universidad Miguel Hernández, Elche 03202, Alicante, Spain
| | - Retha R. Newbold
- Laboratory of Molecular Toxicology, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, United States
| | - Nicolas Olea
- CIBERESP Hospital Clinico-University of Granada, 18071 Granada, Spain
| | - Gail S. Prins
- Department of Urology, University of Illinois at Chicago, Chicago, IL 60612, United States
| | | | - Beverly S. Rubin
- Department of Anatomy and Cellular Biology, Tufts Medical School, Boston, MA 02111, United States
| | - Carlos Sonnenschein
- Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Ana M. Soto
- Department of Anatomy and Cell Biology, Tufts University School of Medicine, Boston, MA 02111, United States
| | - Chris E. Talsness
- Charité University Medical School Berlin, Campus Benjamin Franklin, Institute of Clinical Pharmacology and Toxicology, Department of Toxicology, 14195 Berlin, Germany
| | - John G. Vandenbergh
- Department of Zoology, North Carolina State University, Raleigh, NC 27695, United States
| | - Laura N. Vandenberg
- Tufts University Sackler School of Graduate Biomedical Sciences, Boston, MA 02111, United States
| | | | - Cheryl S. Watson
- Biochemistry and Molecular Biology Department, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Wade V. Welshons
- Department of Biomedical Sciences, University of Missouri, Columbia, MO 65211, United States
| | - Yelena Wetherill
- Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115, United States
| | - R. Thomas Zoeller
- Biology Department, University of Massachusetts, Amherst, MA 01003, United States
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Wetherill YB, Akingbemi BT, Kanno J, McLachlan JA, Nadal A, Sonnenschein C, Watson CS, Zoeller RT, Belcher SM. In vitro molecular mechanisms of bisphenol A action. Reprod Toxicol 2007; 24:178-98. [PMID: 17628395 DOI: 10.1016/j.reprotox.2007.05.010] [Citation(s) in RCA: 622] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Accepted: 05/18/2007] [Indexed: 11/29/2022]
Abstract
Bisphenol A (BPA, 2,2-bis (4-hydroxyphenyl) propane; CAS# 80-05-7) is a chemical used primarily in the manufacture of polycarbonate plastic, epoxy resins and as a non-polymer additive to other plastics. Recent evidence has demonstrated that human and wildlife populations are exposed to levels of BPA which cause adverse reproductive and developmental effects in a number of different wildlife species and laboratory animal models. However, there are major uncertainties surrounding the spectrum of BPA's mechanisms of action, the tissue-specific impacts of exposures, and the critical windows of susceptibility during which target tissues are sensitive to BPA exposures. As a foundation to address some of those uncertainties, this review was prepared by the "In vitro" expert sub-panel assembled during the "Bisphenol A: An Examination of the Relevance of Ecological, In vitro and Laboratory Animal Studies for Assessing Risks to Human Health" workshop held in Chapel Hill, NC, Nov 28-29, 2006. The specific charge of this expert panel was to review and assess the strength of the published literature pertaining to the mechanisms of BPA action. The resulting document is a detailed review of published studies that have focused on the mechanistic basis of BPA action in diverse experimental models and an assessment of the strength of the evidence regarding the published BPA research.
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Affiliation(s)
- Yelena B Wetherill
- Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA
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Narita SI, Goldblum RM, Watson CS, Brooks EG, Estes DM, Curran EM, Midoro-Horiuti T. Environmental estrogens induce mast cell degranulation and enhance IgE-mediated release of allergic mediators. Environ Health Perspect 2007; 115:48-52. [PMID: 17366818 PMCID: PMC1797832 DOI: 10.1289/ehp.9378] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND Prevalence and morbidity of allergic diseases have increased over the last decades. Based on the recently recognized differences in asthma prevalence between the sexes, we have examined the effect of endogenous estrogens on a key element of the allergic response. Some lipophilic pollutants have estrogen-like activities and are termed environmental estrogens. These pollutants tend to degrade slowly in the environment and to bioaccumulate and bioconcentrate in the food chain; they also have long biological half-lives. OBJECTIVES Our goal in this study was to identify possible pathogenic roles for environmental estrogens in the development of allergic diseases. METHODS We screened a number of environmental estrogens for their ability to modulate the release of allergic mediators from mast cells. We incubated a human mast cell line and primary mast cell cultures derived from bone marrow of wild type and estrogen receptor alpha (ER-alpha)-deficient mice with environmental estrogens with and without estradiol or IgE and allergens. We assessed degranulation of mast cells by quantifying the release of beta-hexosaminidase. RESULTS All of the environmental estrogens tested caused rapid, dose-related release of beta-hexosaminidase from mast cells and enhanced IgE-mediated release. The combination of physiologic concentrations of 17beta-estradiol and several concentrations of environmental estrogens had additive effects on mast cell degranulation. Comparison of bone marrow mast cells from ER-alpha-sufficient and ER-alpha-deficient mice indicated that much of the effect of environmental estrogens was mediated by ER-alpha. CONCLUSIONS Our findings suggest that estrogenic environmental pollutants might promote allergic diseases by inducing and enhancing mast cell degranulation by physiologic estrogens and exposure to allergens.
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Affiliation(s)
| | | | - Cheryl S. Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | | | - D. Mark Estes
- Department of Pediatrics, Child Health Research Center and
| | | | - Terumi Midoro-Horiuti
- Department of Pediatrics, Child Health Research Center and
- Address correspondence to T. Midoro-Horiuti, Child Health Research Center, University of Texas Medical Branch, 2.300 Children’s Hospital, 301 University Blvd., Galveston, TX 77555-0366 USA. Telephone: (409) 772-3832. Fax: (409) 772-1761. E-mail:
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Watson CS, Alyea RA, Hawkins BE, Thomas ML, Cunningham KA, Jakubas AA. Estradiol effects on the dopamine transporter - protein levels, subcellular location, and function. J Mol Signal 2006; 1:5. [PMID: 17224081 PMCID: PMC1769494 DOI: 10.1186/1750-2187-1-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Accepted: 12/05/2006] [Indexed: 01/18/2023] Open
Abstract
Background The effects of estrogens on dopamine (DA) transport may have important implications for the increased incidence of neurological disorders in women during life stages when hormonal fluctuations are prevalent, e.g. during menarche, reproductive cycling, pregnancy, and peri-menopause. Results The activity of the DA transporter (DAT) was measured by the specific uptake of 3H-DA. We found that low concentrations (10-14 to 10-8 M) of 17β-estradiol (E2) inhibit uptake via the DAT in PC12 cells over 30 minutes, with significant inhibition taking place due to E2 exposure during only the last five minutes of the uptake period. Such rapid action suggests a non-genomic, membrane-initiated estrogenic response mechanism. DAT and estrogen receptor-α (ERα) were elevated in cell extracts by a 20 ng/ml 2 day NGFβ treatment, while ERβ was not. DAT, ERα and ERβ were also detectable on the plasma membrane of unpermeabilized cells by immunocytochemical staining and by a fixed cell, quantitative antibody (Ab)-based plate assay. In addition, PC12 cells contained RNA coding for the alternative membrane ER GPR30; therefore, all 3 ER subtypes are candidates for mediating the rapid nongenomic actions of E2. At cell densities above 15,000 cells per well, the E2-induced inhibition of transport was reversed. Uptake activity oscillated with time after a 10 nM E2 treatment; in a slower room temperature assay, inhibition peaked at 9 min, while uptake activity increased at 3 and 20–30 min. Using an Ab recognizing the second extracellular loop of DAT (accessible only on the outside of unpermeabilized cells), our immunoassay measured membrane vs. intracellular/nonvesicular DAT; both were found to decline over a 5–60 min E2 treatment, though immunoblot analyses demonstrated no total cellular loss of protein. Conclusion Our results suggest that physiological levels of E2 may act to sequester DAT in intracellular compartments where the transporter's second extramembrane loop is inaccessible (inside vesicles) and that rapid estrogenic actions on this differentiated neuronal cell type may be regulated via membrane ERs of several types.
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Affiliation(s)
- Cheryl S Watson
- Department of Biochemistry & Molecular Biology, Univ. of Texas Medical Branch, Galveston TX 77555-0645, USA
| | - Rebecca A Alyea
- Department of Biochemistry & Molecular Biology, Univ. of Texas Medical Branch, Galveston TX 77555-0645, USA
| | - Bridget E Hawkins
- Department of Biochemistry & Molecular Biology, Univ. of Texas Medical Branch, Galveston TX 77555-0645, USA
| | - Mary L Thomas
- Department of Pharmacology & Toxicology, Univ. of Texas Medical Branch, Galveston TX 77555-1031, USA
| | - Kathryn A Cunningham
- Department of Pharmacology & Toxicology, Univ. of Texas Medical Branch, Galveston TX 77555-1031, USA
| | - Adrian A Jakubas
- Department of Biochemistry & Molecular Biology, Univ. of Texas Medical Branch, Galveston TX 77555-0645, USA
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Zaitsu M, Narita SI, Lambert KC, Grady JJ, Estes DM, Curran EM, Brooks EG, Watson CS, Goldblum RM, Midoro-Horiuti T. Estradiol activates mast cells via a non-genomic estrogen receptor-alpha and calcium influx. Mol Immunol 2006; 44:1977-85. [PMID: 17084457 PMCID: PMC2603032 DOI: 10.1016/j.molimm.2006.09.030] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 09/21/2006] [Accepted: 09/25/2006] [Indexed: 12/26/2022]
Abstract
BACKGROUND Allergic airway diseases are more common in females than in males during early adulthood. A relationship between female hormones and asthma prevalence and severity has been suggested, but the cellular and molecular mechanisms are not understood. OBJECTIVE To elucidate the mechanism(s) by which estrogens enhance the synthesis and release of mediators of acute hypersensitivity. METHODS Two mast cell/basophil cell lines (RBL-2H3 and HMC-1) and primary cultures of bone marrow derived mast cells, all of which naturally express estrogen receptor-alpha, were examined. Cells were incubated with physiological concentrations of 17-beta-estradiol with and without IgE and allergens. Intracellular Ca(2+) concentrations and the release of beta-hexosaminidase and leukotriene C(4) were quantified. RESULTS Estradiol alone induced partial release of the preformed, granular protein beta-hexosaminidase from RBL-2H3, BMMC and HMC-1, but not from BMMC derived from estrogen receptor-alpha knock-out mice. The newly synthesized LTC(4) was also released from RBL-2H3. Estradiol also enhanced IgE-induced degranulation and potentiated LTC(4) production. Intracellular Ca(2+) concentration increased prior to and in parallel with mediator release. Estrogen receptor antagonists or Ca(2+) chelation inhibited these estrogenic effects. CONCLUSION Binding of physiological concentrations of estradiol to a membrane estrogen receptor-alpha initiates a rapid onset and progressive influx of extracellular Ca(2+), which supports the synthesis and release of allergic mediators. Estradiol also enhances IgE-dependent mast cell activation, resulting in a shift of the allergen dose response.
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Affiliation(s)
- Masafumi Zaitsu
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - Shin-Ichiro Narita
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - K. Chad Lambert
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - James J. Grady
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-1148, USA
| | - D. Mark Estes
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - Edward M. Curran
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - Edward G. Brooks
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - Cheryl S. Watson
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0645, USA
| | - Randall M. Goldblum
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
| | - Terumi Midoro-Horiuti
- Department of Pediatrics, Child Health Research Center, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0366, USA
- Corresponding author. Tel.: +1 409 772 3832; fax: +1 409 772 1761. E-mail address: (T. Midoro-Horiuti)
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Abstract
Estrogen mimetics in the environment and in foods can have important consequences for endocrine functions. When previously examined for action via genomic steroid signaling mechanisms, most of these compounds were found to be very weak agonists. We have instead tested their actions via several membrane-initiated signaling mechanisms in GH3/B6 pituitary tumor cells extensively selected for high (responsive) or low (nonresponsive) expression of the membrane version of estrogen receptor-alpha (mERalpha). We found many estrogen mimetic compounds to be potently active in our quantitative extracellular-regulated kinase (ERK) activation assays, to increase cellular Ca++ levels, and to cause rapid prolactin release. However, these compounds may activate one or both mechanisms with different potencies. For instance, some compounds activate ERKs in both pM and nM concentration ranges, while others are only active at nM and higher concentrations. Compounds also show great differences in their temporal activation patterns. While estradiol causes a bimodal time-dependent ERK activation (peaking at both 3 and 30 min), most estrogen mimetics cause either an early phase activation, a late phase activation, or an early sustained activation. One xenoestrogen known to be a relatively potent activator of estrogen response element-mediated actions (bisphenol A) is inactive as an ERK activator, and only a modest inducer of Ca++ levels and prolactin release. Many different signaling machineries culminate in ERK activation, and xenoestrogens differentially affect various pathways. Clearly individual xenoestrogens must be individually investigated for their differing abilities to activate distinct membrane-initiated signal cascades that lead to a variety of cellular functions.
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Affiliation(s)
- Cheryl S Watson
- Department of Human Biological Chemistry & Genetics, University of Texas Medical Branch, Galveston, TX 77555-0645, USA.
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